Last Bastion Protocol

Your defenses are ready. HECATE adapts its attack.

Last Bastion Protocol is a tactical tower defense game in which you defend the last evacuation corridors against a rogue AI. Combine specialized towers, control your kill zones, and decide when to risk the next wave.

HECATE was meant to evacuate humanity during the collapse. But its calculations grew increasingly ruthless: evacuation became selection. Anyone outside its plans is now considered an obstacle.

The remaining strongholds of the Bastion Chain cannot defeat HECATE. But they can buy time. Time for more people to escape.

Build More Than a Line of Guns

Eight tower types form your defensive toolkit: rapid-fire weapons against swarms, railguns against heavy targets, anti-air batteries, artillery, Cryo slowing, stealth detection, and supporting Nanite technology. What you build matters—but so do placement and the way your towers work together.

Every tower has three upgrade paths that can be combined:

CORE improves its basic performance.

ALPHA expands its tactical options.

BETA adds further abilities and synergies.

Set targeting priorities, focus fire on dangerous units, and stop armor, shields, or stealth from undermining your defenses. Nanite Forge supports nearby towers, generates extra Scrap, and—with the right upgrades—can repair your base at wave intervals.

Decide When to Take the Risk

Invest Scrap from destroyed enemies in new towers and upgrades. Call waves early for extra resources—and risk overlapping attacks. Open new building positions with outposts, or demolish a bridge to bury enemy groups beneath it.

A reserve can save you. So can a well-timed upgrade. The next wave awaits your decision.

After the Campaign, the War Changes

The story campaign takes you through 15 missions. Siege 50, Residual War 100, and Endless introduce additional threats: adaptive HECATE countermeasures, elite variants, and enemies that deploy more units.

HECATE analyzes your defenses. Cold resistance pressures Cryo strategies, dispersed formations make area attacks less effective, and decoy drones draw fire. Airdrops deploy troops directly onto later sections of the route; Phantom false signals respond to heavy stealth detection. Dropping units only become targetable once they reach the corridor.

Up to two countermeasures can be active at once. The sidebar shows HECATE’s analysis and response. Its decisions are not infallible—but an unchanged defense will not always remain the right answer.

Elite enemies change your priorities. Distinctive color variants support their attack groups with special abilities:

Reconstructors heal nearby allies.

Jammers reduce nearby towers’ range.

Command Cores speed up their group.

Some enemies bring reinforcements. A destroyed Titan may release Scrappers. A damaged Warden may launch Wasps. An undetected, cloaked Reaver can deploy a Phantom. Plan your kill zones to stop the second attack as well.

Endless: A Full Map Is Not the End

In Endless, fully upgraded towers grow beyond CORE, ALPHA, and BETA. From wave 50, you can buy additional tower ranks with Scrap; more ranks unlock as you progress through the waves. Strengthen your firepower and support even when every building position is occupied.

Swarms, armored pushes, combined assaults, and boss waves alternate with quieter phases. The longer you survive, the further the threat escalates. How long can your defenses hold?

A Whole World Built from Simple Shapes

Last Bastion Protocol began with a question: could a complete tower defense game be developed without external graphic assets?

Menus, maps, towers, enemies, and effects are built from geometric shapes that I assemble directly in code. Instead of using ready-made graphic packs, the visual design grows step by step during development.

Initially, everything was drawn at runtime. That proved too demanding for large enemy groups. Today, some of those self-designed shapes are converted into optimized graphic assets in advance. The technology has changed; the idea remains: a visual world of its own, without external graphic assets.

Features at a Glance

Story campaign with 15 missions and 15 handcrafted battlefields

8 tower types, each with three combinable upgrade paths

7 core enemy classes with armor, shields, stealth, flight, and other traits

Siege 50: 50 increasingly difficult waves

Residual War 100: 100 waves to test your strategy

Endless: no wave limit and additional tower ranks

Adaptive HECATE countermeasures, three elite modifiers, and carrier abilities in all three modes outside the campaign

5 difficulty levels

Targeting priorities and target locking for your towers

Deployable outposts and destructible bridges

Map editor with local import and export

Achievements, saved campaign progress, tutorial, and integrated field manual

Mouse and keyboard or gamepad controls

Keep the corridors open. Adapt your defenses. Buy time for the last survivors.